Around 39 people at Malaysia’s Kuala Lumpur international airport fell ill on Thursday after a gas leak at an aircraft engineering facility, but no passengers were affected and there were no flight disruptions, the fire department said.

The Selangor state fire department said it received an emergency call regarding a chemical leak at the Southern Support Zone Sepang Aircraft Engineering facility at 11.23 a.m. (0323 GMT) and dispatched its personnel along with a hazardous materials team.

The engineering facility is separate to the passenger terminal and those affected by the gas worked for three companies operating there, the fire department said in a statement.

Thirty nine people complained of dizziness and nausea, with 14 sent to the air disaster unit to receive treatment while one was hospitalised, the department said.

There was no wider risk to public safety, it added.

The chemical was later identified as methyl mercaptan, added to liquefied petroleum gas as an odorant, coming from an unused tank at the facility, the department said.

The leak was being patched up, and the tank would be dismantled and disposed of, it said.